Objective To study the influence of oxybutynin, tolterodine or trospium chloride, anticholinergics used to treat bladder overactivity, on sleep and the cognitive skills of healthy volunteers aged greater than or equal to 50 years. Subjects and Methods In a randomized, double-blind, placebo-controlled study with a crossover design, 24 healthy sleepers (12 men and 12 women) aged 51-65 years underwent polysomnographic recordings and cognitive tests in a sleep laboratory. Study medications were given as a single dose containing the total recommended daily dose. Results There was a significant reduction in rapid-eye movement (REM) sleep of approximate to 15% and a slightly (but not significantly) greater REM latency after oxybutynin and tolterodine than with placebo. After trospium chloride, REM duration and latency were comparable with placebo. There was no effect of the tested anticholinergics on cognitive and subjective sleep variables. Conclusion Individuals aged greater than or equal to 50 years had a more distinct impairment of REM sleep after oxybutynin and tolterodine than had young people, but the reduction in REM sleep did not reach a pathological degree in this single-dose study. There was no apparent impairment of concentration or cognitive function, but impairment of cognitive function and neuropsychological side-effects cannot be excluded, especially when elderly patients with impaired REM sleep from various psychiatric diseases (e.g. depression) and/or sleep disturbances are given oxybutynin or tolterodine in long-term treatment.